New Rotary Shouldered Connection Expands Capability of ERD Operation

Abstract

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE/IADC 168049, “New Rotary Shouldered Connection Expands the Capability of World-Record ERD Operation,” by S.R. Sanford, SPE, and M.W. Walker, SPE, ExxonMobil; and J.N. Brock, M.J. Jellison, SPE, and A. Muradov, SPE, NOV Grant Prideco, prepared for the 2014 SPE/IADC Drilling Conference and Exhibition, Fort Worth, Texas, USA, 4–6 March. The paper has not been peer reviewed. Eight of the world’s 10 longest wells have been drilled by ExxonMobil as operator of the Sakhalin-1 project in Russia. Components and drilling tools involved in the well design are evaluated and redesigned throughout the program to maximize penetration rate and reduce flat time. Drillstring-torque capacity was recognized as a limiter for increasing penetration rate and for reaching total measured depth capability. The operator consequently sought an alternative drillpipe connection with higher torque capacity. Introduction The Sakhalin-1 project comprises the Chayvo, Odoptu, and Arkutun Dagi fields off the east coast of Sakhalin Island, Russian Federation (Fig. 1). Development drilling at the Chayvo field started in 2003 with extended-reach wells drilled from an onshore location with the Yastreb drilling rig. In 2005, further development drilling commenced from the offshore Orlan platform site. Subsequently, in 2008, the Yastreb rig was moved approximately 75 km north to the Odoptu onshore wellsite and drilled nine extended-reach-drilling (ERD) wells as part of the initial-stage development of Odoptu. During the Odoptu campaign, it was determined that a higher-torque 5?-in. drillpipe connection with good runnability was needed. Following the Odoptu campaign, the Yastreb rig was moved back to the Chayvo onshore wellsite in 2011 for further development and infill drilling of the Chayvo reservoirs. Limiter Identification During the first drilling campaign at Chayvo, available topdrive torque limited drilling performance in the long production hole section (>3000 m). Installation of a new topdrive capable of continuous torque in excess of 90,000 lbf-ft at 140 rev/min eliminated this limiter. During the subsequent Odoptu drilling campaign, the 5?-in. drillpipe connection was identified as a new limiter affecting rate of penetration (ROP) and torque operating margin in the production hole section.